1. Field of the Invention
The present invention relates to a tool changer of a machine tool in which a spindle is disposed on a bed and a machining area of the spindle is surrounded by a cover.
2. Description of the Related Art
An example of a machine tool of this type is structured such that a spindle headstock is fixedly disposed on a bed, a lower tool post and an upper is tool post are disposed on a machine outer side and a machine inner side of an axis of the spindle headstock respectively to be movable in an X-axis direction and a Z-axis direction, and the lower and upper tool posts machine a workpiece.
As an example of a tool changer of the above-described machine tool, proposed is a structure in which a tool change opening part is formed in a cover covering a tool magazine, a door opening/closing the opening part is disposed, and at the time of tool change, the door is opened and a preceding-process tool is changed to a subsequent-process tool (see, for example, Patent document 1).
[Patent document 1] Japanese Patent Application Laid-open No. Hei 6-106438
In view of enhancing machining efficiency, a tool of the upper tool post is sometimes changed while a workpiece is machined by the lower tool post. In such a case, the aforesaid conventional tool changer changes the tool while the opening of the cover is kept open, so that chips may possibly scatter from the opening to the outside during the tool change and in some cases, the scattered chips adhere to a sliding portion, a tool gripper portion, and so on of the tool changer.